Native dialogs

Native dialogs are dialogs which can be created and used through APIs which are provided by the operating system. Some dialogs are modal and block all interaction with the parent window, and some are modeless and behave mostly like regular windows.

Some examples of native dialogs are:
 * File dialogs
 * The "about" dialog
 * Modal "confirmation" dialogs

There are a couple of crates which allow you to create different kinds of dialogs.